adding in stats to keyv (#1001)

* adding in stats to keyv

* adding in stats option

* getting errors to work

* moving to counts as properties

* adding in stats

packages/keyv/src/index.ts

@@ -1,6 +1,7 @@
 import JSONB from 'json-buffer';
 import HooksManager from './hooks-manager';
 import EventManager from './event-manager';
+import StatsManager from './stats-manager';
 
 export type DeserializedData<Value> = {
 	value?: Value;
@@ -71,6 +72,8 @@ export interface Options {
 	compression?: CompressionAdapter;
 	/** Specify an adapter to use. e.g `'redis'` or `'mongodb'`. */
 	adapter?: 'redis' | 'mongodb' | 'mongo' | 'sqlite' | 'postgresql' | 'postgres' | 'mysql';
+	/** Enable or disable statistics (default is false) */
+	stats?: boolean;
 }
 
 type IteratorFunction = (arg: any) => AsyncGenerator<any, void>;
@@ -115,6 +118,7 @@ class Keyv extends EventManager {
 	opts: Options;
 	iterator?: IteratorFunction;
 	hooks = new HooksManager();
+	stats = new StatsManager(false);
 	constructor(uri?: string | Omit<Options, 'store'>, options_?: Omit<Options, 'store'>) {
 		super();
 		options_ = options_ ?? {};
@@ -157,6 +161,10 @@ class Keyv extends EventManager {
 				this.iterator = this.generateIterator(this.opts.store.iterator.bind(this.opts.store));
 			}
 		}
+
+		if (this.opts.stats) {
+			this.stats.enabled = this.opts.stats;
+		}
 	}
 
 	generateIterator(iterator: IteratorFunction): IteratorFunction {
@@ -234,6 +242,10 @@ class Keyv extends EventManager {
 				const deserializedRows = await Promise.allSettled(promises);
 				const result = deserializedRows.map(row => (row as PromiseFulfilledResult<any>).value);
 				this.hooks.trigger(KeyvHooks.POST_GET_MANY, result);
+				if (result.length > 0) {
+					this.stats.hit();
+				}
+
 				return result;
 			}
 
@@ -263,6 +275,10 @@ class Keyv extends EventManager {
 			}
 
 			this.hooks.trigger(KeyvHooks.POST_GET_MANY, result);
+			if (result.length > 0) {
+				this.stats.hit();
+			}
+
 			return result as (Array<StoredDataNoRaw<Value>> | Array<StoredDataRaw<Value>>);
 		}
 
@@ -271,15 +287,18 @@ class Keyv extends EventManager {
 		const deserializedData = (typeof rawData === 'string' || this.opts.compression) ? await this.opts.deserialize!<Value>(rawData as string) : rawData;
 
 		if (deserializedData === undefined || deserializedData === null) {
+			this.stats.miss();
 			return undefined;
 		}
 
 		if (isDataExpired(deserializedData as DeserializedData<Value>)) {
 			await this.delete(key);
+			this.stats.miss();
 			return undefined;
 		}
 
 		this.hooks.trigger(KeyvHooks.POST_GET, {key: keyPrefixed, value: deserializedData});
+		this.stats.hit();
 		return (options && options.raw) ? deserializedData : (deserializedData as DeserializedData<Value>).value;
 	}
 
@@ -307,6 +326,7 @@ class Keyv extends EventManager {
 		value = await this.opts.serialize!(value);
 		await store.set(keyPrefixed, value, ttl);
 		this.hooks.trigger(KeyvHooks.POST_SET, {key: keyPrefixed, value, ttl});
+		this.stats.set();
 		return true;
 	}
 
@@ -330,6 +350,7 @@ class Keyv extends EventManager {
 		const keyPrefixed = this._getKeyPrefix(key);
 		const result = store.delete(keyPrefixed);
 		this.hooks.trigger(KeyvHooks.POST_DELETE, result);
+		this.stats.delete();
 		return result;
 	}
 

packages/keyv/src/stats-manager.ts

@@ -0,0 +1,55 @@
+import EventManager from './event-manager';
+
+class StatsManager extends EventManager {
+	public enabled = true;
+
+	public hits = 0;
+	public misses = 0;
+	public sets = 0;
+	public deletes = 0;
+	public errors = 0;
+
+	constructor(enabled?: boolean) {
+		super();
+		if (enabled !== undefined) {
+			this.enabled = enabled;
+		}
+
+		this.reset();
+	}
+
+	hit() {
+		if (this.enabled) {
+			this.hits++;
+		}
+	}
+
+	miss() {
+		if (this.enabled) {
+			this.misses++;
+		}
+	}
+
+	set() {
+		if (this.enabled) {
+			this.sets++;
+		}
+	}
+
+	delete() {
+		if (this.enabled) {
+			this.deletes++;
+		}
+	}
+
+	reset() {
+		this.hits = 0;
+		this.misses = 0;
+		this.sets = 0;
+		this.deletes = 0;
+		this.errors = 0;
+	}
+}
+
+export default StatsManager;
+module.exports = StatsManager;

packages/keyv/test/stats-manager.test.ts

@@ -0,0 +1,54 @@
+import test from 'ava';
+import KeyvStatsManager from '../src/stats-manager';
+
+test('will initialize with correct stats at zero', t => {
+	const stats = new KeyvStatsManager();
+	t.is(stats.hits, 0);
+});
+
+test('will increment hits', t => {
+	const stats = new KeyvStatsManager();
+	stats.hit();
+	t.is(stats.hits, 1);
+});
+
+test('will increment misses', t => {
+	const stats = new KeyvStatsManager();
+	stats.miss();
+	t.is(stats.misses, 1);
+});
+
+test('will increment sets', t => {
+	const stats = new KeyvStatsManager();
+	stats.set();
+	t.is(stats.sets, 1);
+});
+
+test('will increment deletes', t => {
+	const stats = new KeyvStatsManager();
+	stats.delete();
+	t.is(stats.deletes, 1);
+});
+
+test('will reset stats', t => {
+	const stats = new KeyvStatsManager();
+	stats.hit();
+	stats.miss();
+	stats.set();
+	stats.delete();
+	t.is(stats.hits, 1);
+	t.is(stats.misses, 1);
+	t.is(stats.sets, 1);
+	t.is(stats.deletes, 1);
+	stats.reset();
+	t.is(stats.hits, 0);
+	t.is(stats.misses, 0);
+	t.is(stats.sets, 0);
+	t.is(stats.deletes, 0);
+});
+
+test('will not increment hits if disabled', t => {
+	const stats = new KeyvStatsManager(false);
+	stats.hit();
+	t.is(stats.hits, 0);
+});

packages/keyv/test/test.ts

@@ -608,3 +608,20 @@ test.serial('Keyv has should return true or false on Map', async t => {
 	await snooze(1100);
 	t.is(await keyv.has('foo'), false);
 });
+
+test.serial('Keyv opts.stats should set the stats manager', t => {
+	const keyv = new Keyv({stats: true});
+	t.is(keyv.stats.enabled, true);
+});
+
+test.serial('Keyv stats enabled should create counts', async t => {
+	const keyv = new Keyv({stats: true});
+	await keyv.set('foo', 'bar');
+	await keyv.get('foo');
+	await keyv.get('foo1');
+	await keyv.delete('foo');
+	t.is(keyv.stats.hits, 1);
+	t.is(keyv.stats.misses, 1);
+	t.is(keyv.stats.deletes, 1);
+	t.is(keyv.stats.sets, 1);
+});